From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9E86FC6FD1F for ; Wed, 22 Mar 2023 20:01:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231486AbjCVUBS (ORCPT ); Wed, 22 Mar 2023 16:01:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231317AbjCVUA0 (ORCPT ); Wed, 22 Mar 2023 16:00:26 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E99F62B6B; Wed, 22 Mar 2023 12:58:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 27797B81DEC; Wed, 22 Mar 2023 19:58:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27A50C4331D; Wed, 22 Mar 2023 19:58:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679515104; bh=rWaeNrrF5M3V94CkeClxm/OUD5fvq2UHmG8t9yd/ndk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iaj+UdDDv/04tQvfKG3r4kAY6GSyCsmws+aYwIGemWyFaLf5FUO7+lJHO8STl4jgw 1zVp1VA0J2JOjfIdJN8jqEJ8I6GpH2nAEr5BCH0t0l/+9uPvI0DwuW1PihbFciitZY QCwbw+DqNNkPRQkFwVPFpfc0QuYoPtSpPudkg16+xlOq6GGtLuEcfTYDx7//zQqNZe ZLAg2cOxKHY+FPGCGTOJSFsO1FPs0p7iw6JF6DaKlBzJNgAXwpwFygCBGfGHTaNqPu AsbQvHtrRl9FnbgRZ8/K8AA/vuT0TMHg1Fiv92eS5NSGH0YRQ+iv28zsV2oqtvRrZs fTdl2xG081USg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: NeilBrown , Dan Carpenter , Song Liu , Sasha Levin , linux-raid@vger.kernel.org Subject: [PATCH AUTOSEL 6.2 22/45] md: avoid signed overflow in slot_store() Date: Wed, 22 Mar 2023 15:56:16 -0400 Message-Id: <20230322195639.1995821-22-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230322195639.1995821-1-sashal@kernel.org> References: <20230322195639.1995821-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: NeilBrown [ Upstream commit 3bc57292278a0b6ac4656cad94c14f2453344b57 ] slot_store() uses kstrtouint() to get a slot number, but stores the result in an "int" variable (by casting a pointer). This can result in a negative slot number if the unsigned int value is very large. A negative number means that the slot is empty, but setting a negative slot number this way will not remove the device from the array. I don't think this is a serious problem, but it could cause confusion and it is best to fix it. Reported-by: Dan Carpenter Signed-off-by: NeilBrown Signed-off-by: Song Liu Signed-off-by: Sasha Levin --- drivers/md/md.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/md/md.c b/drivers/md/md.c index 272cc5d14906f..beab84f0c585c 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3131,6 +3131,9 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len) err = kstrtouint(buf, 10, (unsigned int *)&slot); if (err < 0) return err; + if (slot < 0) + /* overflow */ + return -ENOSPC; } if (rdev->mddev->pers && slot == -1) { /* Setting 'slot' on an active array requires also -- 2.39.2